Why are prefixes often added to si units? a. to convert to other systems of units b. to communicate very large or small measurements c. to account for errors in measurement d. to indicate the measuring tool that was used

The correct answer is (B).

Explanation:

A prefix may be added to a unit to produce a multiple of the original unit. All multiples are integer powers of ten. For example, kilo- denotes a multiple of a thousand and milli- denotes a multiple of a thousandth; hence there are one thousand millimetres to the metre and one thousand metres to the kilometre. The prefixes are never combined: a millionth of a kilogram is a milligram not a microkilogram.

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